Biological agents of disease Flashcards Preview

Pathobiology > Biological agents of disease > Flashcards

Flashcards in Biological agents of disease Deck (30):
1

What is the structure of an influenza virion and how does it enter the cell?

- Enveloped
- RNA virus
- Endocytosis of whole virion, forming enocytic vesicles

- Vesicle acidified and the envelope fuses with the membrane
- Coat protein and RNA released into the cell separately

2

What can listeria monocytogenes do?

- Creates an actin tail, which propells the bacterium around the cell
- May push into the plasma membrane of neighbouring cell and can enter the cell
- No need to leave cell

3

What is the zipper mechanism?

- Receptors on the bacterium interact with receptors on the cell
- Cascade causes the engulfing of the bacterium

4

How does c-src proto-oncogene become an oncogene?

- Integrated into the viral genome
- Changed as integrated (v-src)
- No C terminus so can't be phosphorylated to turn off the kinase

5

What is class II of the Baltimore classification?

ssDNA, either + or -
- uses host DNA-d-DNA-p to make double strand

6

What is the structure of a adenovirus virion and how does it enter the cell?

- DNA virus
- No envelope
- Endocytosis
- Into early endosome
- Lyses the membrane
- Enters the nucleus

7

What secretes listeriolyisin O and what does this do?

- Listeria monocytogenes (taken up by the zipper mechanism)

- Breaks down the phagosome (low pH)
- But broken down in the cytoplasm (high pH)

8

What does P53 protein do?

Prevents transcription, safety mechanism

9

What does Rb protein do?

Binds to cell proliferation factor, preventing proliferation

10

Which bacteria has pathogenicity islands?

Salmonella

11

What class of virus is influenza?

V

12

What does Leguonella pneumophilla do?

- When inhaled it is phagocytosed
- Replicates inside the phagosome and prevents fusion with the endosome

13

What is the structure of a HIV virion and how does it enter the cell?

- Enveloped
- RNA virus
- Envelope fuses with host membrane

14

What is class VI of the Baltimore classification?

RETROVIRUSES
1) + ssRNA
2) Carries reverse transcriptase to make - strand cDNA
3) Makes dsDNA
4) Integrates into host genome
5) Uses host DNA-d-RNA-p to make coat protein
6) Moves into other cells

15

What is class V of the Baltimore classification?

- strand ssRNA
Carries RNA-d-RNA-p
Makes + strand RNA

16

What does the Pertussis toxin do?

Interferes with chemotactic pathways of the neutorphills

17

What does the type III secretion system do?

- Acts like a syringe
- Injects toxins/ effector proteins into another cell

18

Which bacteria has virulence plasmid?

Shigella

19

2 examples of a retrovirus?

AIDS
Leukemia

20

What is class IV of the Baltimore classification?

+ strand ssRNA
Makes RNA-d-RNA-p

21

How do papillovirus cause cancer?

E6 binds to P53
E7 binds to Rb

- Inactivate them, too much proliferation

22

What is class I of the Baltimore classification?

dsDNA

23

What class of virus is polio virus?

IV

24

How does E coli use the type III secretion system?

- Injects Tir into the cell
- Tir integrates into the plasma membrane of the host cell and interacts with bacteria

- Tir phosphorylated, causing actin polymmerisation

25

What is needed to make the + strand of RNA?

The negative strand of DNA

26

What is the structure of a poliovirus virion and how does it enter the cell?

- RNA virus
- No envelope
- Endocytosis into endocytic vesicle
- Creates pore
- Allows virus out

27

What class of virus are adenoviruses and papilloma?

I

28

What is class VII of the Baltimore classification?

dsDNA
Contains reverse transcriptase
DNA --> genomic RNA

29

What is class III of the Baltimore classification?

- Segmented genomes of dsRNA (can make 1-2 proteins)
- Carries RNA-d-RNA-p to make + strand RNA

30

What is the trigger mechanism?

- Type III secretion system
- Cascade